Vacuum discharge-tube for lighting purposes.



G. CLAUDE. VACUUM DISCHARGE TUBE FOR LIGHTING PURPOSES.

- APPLICATION FILED 11:12.27, 1911.

/0 x/efi for; farqes a 0019 Emma Mar. 16, R9115.

up by the walls or the electrodes of the tube. It is only after thelapse of a very long time (two or three hours or even longer), combinedwith the vigorous heating of the tube by the passage of the current,that the splendid luminescence of the unabsorbed neon appears in all itsbrilliancy and that the luminescent tube can be separated at S from thecooled carbon receptacle R. It will of course be understood that anumber of tubes can be connected up to the same carbon receptacle. Onthe other hand, if the tube is very long, a plurality of appropriatelydistributed carbon receptacles can be connected to a single tube.Generally speaking, the arrangement may be rendered more industrialWithout effecting the principle of the invention, the essential featureof which consists in the means for enabling the neon to be freed, duringthe treatment itself, from the impurities that it contains or that areliberated.

The light produced by neon always contains a large excess of red rays.Mercury, by reason of its remarkable capacity for luminescence and itsgreen radiation, which is almost complementary to that of neon, might beadvantageous for correcting this light; it is however, found that if theleast globule of mercury is introduced into the tube, as soon as thelatter becomes heated by its operation, the tube is invaded by so muchgreen mercury light that it is diliicult to discern even with thespectroscope a few rays of the neon. It is, however, possible to employcorrecting tubes arranged alongside the neon tubes. The arrangementsindicated above permit of obtaining tubes of high luminous power whichare capable of replacing arc lamps. With tubes from 40 to 45 mm. indiameter, for example, there is no difliculty in attaining luminouspowers that have never hitherto been approached, namely from 300 to 400candle power per meter of tube. My neon tubes are also applicable to theproduction of tubes of low luminous power, suitable for replacingincandescent electric lamps, for example. This result is so much themore important in that the great length of the tubes, the specialproperties of the light and the diversity of the forms that it ispossible to give to these tubes by winding them spirally, bending themor forming various designs with them, such as letters for luminousadvertising signs and the like, render it possible to obtain decorativeor utilitarian effects of a very special character.

What I claim and desire to secure by Letters Patent of the United Statesis 1. In the manufacture of neon vacuum discharge tubes for lightingpurposes in which approximately pure neon is introduced to the tubeunder reduced pressure, the improvement which consists in connectthetube under ing the tube to a device into which the molecu es of theatmosphere of the tube can pass in succession by diffusion and whichcontains material capable of absorbing the impurities contained in theneon, and then passing an intermittent current through the tu e.

2. In the manufacture of neon vacuum discharge tubes for lightingpurposes in which the gases contained in the tube are exhausted byavacuum pump and in which approximately pure neon is introduced to thetube under reduced pressure, the improvement which consists inconnecting the tube to a device into which the molecules of 3 theatmosphere of the tube can pass in suc' cession by diffusion and whichcontains material capable of absorbing the impurities contained in theneon, then passing an intermittent current through the tube, whereby theneon is purified by the slow action of diffusion and by the forcing ofthe gases into the absorption device due to the expansion of the gasesby the electric current.

3. In the manufacture of neon vacuum discharge tubes for lightingpurposes in which the gases contained in the tube are exhausted by avacuum pump and in which approximately pure neon is introduced to thetube under reduced pressure, the improvement which consists inconnecting the tube to a cooled carbon-containing receptacle maintainedat a very low temperature for absorbing by diffusion the impuritiescontained in the neon, then passingan inter- 100 mittent current throughthe tube whereby the impuritiesin the neon and those liberated from theelectrodes and the walls of the tube are absorbed by the slow action ofdiffusion and by the forcing of the gases 05 into the absorption devicedue to the expansion of the gases by the electric current.

.4. In the manufacture of neon vacuum discharge tubes for lightingpurposes in which the gases contained in the tube are 110 exhausted by avacuum pump and in which approximately pure neon is introduced toreduced pressure, the improvement which consists in connecting the tubeto a device into which the molecules of 115 the atmosphere of the tubecan pass in succession by diffusion and which contains material capableof absorbing the impurities contained in the neon, then passing anintel-mittent current through the tube, where- 120 by the neon ispurified by the slow action of diffusion and by the forcing of the gasesinto the absorption device due to the expansion of the gases by theelectric current, and finally separating the tube from the ab- 1:5sorption device without destroying the vacuum.

5. In the manufacture of neon vacuum discharge tubes for lightingpurposes in which the gases contained in the tube are 1 men ene tubeunderreuced pressure, the improvement which consists in connecting thetubetoe cooled carbon-containing receptacle mamtd at e Veg! lowtemperature for abeorbing by di 11 tieined in the neon, then passing amintermittent current through the tube whereby the impurities in the neonand those libereted from the electrodes and the walls of the tube areebsorhefl by the slow action of sion the impurities 0010- difiusiou endby the forein of the ees ieto the absorption device ue to the expensionof the gases by the electric current, and finally segemtimg the tubefrom the ebsorption device Without destroying the vacuum.

In testimony whereof ]i chi my signeture in presence 0t two Witnesses.-

GEQRGES CLAUDE, Witnesses:

Pmwm Home, DEAN B. MAeoN.

